1. Field of the Invention
The present invention relates generally to tools used in the construction industry. More particularly, the invention concerns a specially designed spirit level for use by plumbers having replaceable spirit vials and including a novel connector mechanism for releasably connecting the level to the structure to be leveled.
2. Discussion of the Prior Art
Spirit levels of various designs have been suggested in the past and are widely used by construction workers to determine the orientation of a particular structure or surface with respect to a reference axis. A typical spirit level generally comprises an elongated body that has a pair of opposing, generally parallel working surfaces and includes a plurality of openings having spirit vials permanently secured therein. The spirit vials are typically aligned in different directions relative to the working surfaces and function to indicate the orientation of a structure. For example, one vial may be aligned in a direction perpendicular to the working surfaces, another may be aligned in a direction parallel to the working surfaces and a third may be aligned in an angular direction. Typically, the vial contains a fluid and a spirit, and the user views the position of the spirit within the vial to determine the position of the tool relative to the working surfaces.
A novel and highly useful level construction is disclosed in U.S. Pat. No. 7,536,798 issued to the present inventor. This patent, which is entitled “Multiple Angle Compact Spirit Level”, describes a level with a generally U-shaped or round, rigid frame. The outer surface of the level is comprised of a number of planar reference faces that are at different fixed angles with respect to the spirit vial mounted within the frame
Another useful level construction is disclosed in U.S. Pat. No. 7,802,372 also issued to the present inventor. This patent, which is entitled “Removable Laser Base Attachment for Spirit Levels”, describes a spirit level that includes a body, a laser beam generator, and a removable securement. The body has a flat top surface that the level is secured to and a bottom surface that is flat and parallel to the top surface. A laser diode mounted in a module emits a visible laser beam upon application of power from a battery that is controlled by a switch. The module, batteries, and switch are mounted in a through bore in the body. The laser base is removably secured to the spirit level by any manner appropriate to the shape of the level. In one such securement, the level has a T-shaped cross-section and the body has a complementary slot into which the level slides. When the level reference surface abuts the top surface of the laser base, a thumb screw is tightened to frictionally secure the level in the base.